The invention relates generally to fiber optic splice closures, and in particular to a fiber optic splice closure that includes a frame for receiving couplers and a splice organizer on the same splice tray.
Fiber optic data and communication systems employ splice closures at various points along a distribution network. A typical splice closure will be used to connect drop cables to an express cable. The drop cables may lead to individual businesses or dwellings. The splice closure has a frame with an end cap on one or both ends. The frame has provisions for receiving splice trays and storing slack fiber optic cable. The express cable typically has a jacket surrounding a number of buffer or express tubes. Each express tube has a plurality of optical fibers, normally from six to about twelve. The jacket of the express cable will be stripped off and sealed around an aperture in the end cap. Some of the express tubes will be cut and extend between the end cap and splice trays attached to the frame. Other express tubes remain uncut and will pass in a loop around the frame and back out the end cap.
The splice trays have splice organizers comprising splice holders for retaining splices that connect individual express fibers from the express tubes to drop cable fibers. The drop cable fibers are encased within transport tubes and lead to a drop cable that is sealed in an aperture in the end cap.
Coupler cassettes are also employed in fiber optic data and communications systems. A coupler cassette is a flat container for housing couplers, splice holders and slack areas for retaining slack optical fibers. A coupler joins one input optical fiber to two or more output optical fibers, thereby splitting the light being transmitted through a fiber into two or more fibers. In at least one instance, couplers have been utilized in connection with a splice closure of the type described above. In this instance, the individual couplers, splice holders, and fibers were all located in the coupler module. Locating the splice holders in the coupler module with the couplers, however, results in a complex and confusing splicing area.
The splice closure of the present invention includes a frame and an end cap on one end with apertures for the passage of fiber optic cables. At least one coupler cassette is removably mounted to the frame. The coupler cassette houses at least one coupler that connects an input optical fiber to a plurality of output optical fibers. At least one splice organizer comprising a plurality of splice holders is also carried by the frame exterior of the coupler cassette on the same splice tray. The splice holders retain splices of optical fibers leading to and from the coupler cassette. A housing encloses the frame, coupler cassette and splice organizer.
The splice closure preferably further has an optical fiber storage tray carried by the frame adjacent the splice organizer. The optical fiber storage tray stores unused optical fibers from the express tubes and drop cable tubes. Preferably the optical fiber storage tray is hinged so that it will move between a closed position overlying the splice organizer and an opened position exposing the splice organizer.
The coupler cassette and the splice organizer are preferably mounted on a main splice tray of the frame. In one embodiment, the main splice tray is generally planar and is affixed to the frame. In another embodiment, the main splice tray is removable from the frame and fits within a slot formed in the frame.
Preferably, a plurality of coupler cassettes will be utilized with each splice closure. The coupler cassettes may be stacked on one another in a subassembly. The coupler cassettes connect optical fibers such that one input optical fiber entering the coupler cassette subassembly results in a plurality of output optical fibers leaving the coupler cassette subassembly.